Allowance for loan losses ending allowance balance attributable to loans.

No definition available.

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- Definition

Financing receivable allowance for credit losses modifications recorded investment.

+ References

No definition available.

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- Definition

Financing receivables allowance for credit loss additional information for loans.

+ References

No definition available.

+ Details

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Period Type:	instant

- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Loans - Allowance for Loan Losses and Recorded Investment in Loans by Portfolio Segment (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	$ 22	$ 47
Allowance for loan losses, Collectively evaluated for impairment	14,288	13,957
Allowance for loan losses, Modified in a troubled debt restructuring	6,446	5,689
Acquired with deteriorated credit quality	20,756	19,693	$ 16,546	$ 16,330
Loans:
Loans individually evaluated for impairment	3,310	1,238
Loans collectively evaluated for impairment	2,257,939	2,130,228
Acquired with deteriorated credit quality	1,467,990	1,349,203
Loans modified in a troubled debt restructuring	17,360	17,303
Total ending loans balance	2,279,753	2,149,848
Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	1,144	1,079
Commercial, Industrial, and Agricultural [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	20	47
Allowance for loan losses, Collectively evaluated for impairment	5,984	5,868
Allowance for loan losses, Modified in a troubled debt restructuring	278	245
Acquired with deteriorated credit quality	6,282	6,160	4,785	5,428
Loans:
Loans individually evaluated for impairment	1,418	1,187
Loans collectively evaluated for impairment	766,905	742,738
Acquired with deteriorated credit quality	773,473	749,138
Loans modified in a troubled debt restructuring	5,150	5,213
Total ending loans balance	773,473	749,138
Commercial, Industrial, and Agricultural [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Commercial Mortgages [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	2	0
Allowance for loan losses, Collectively evaluated for impairment	3,850	3,563
Allowance for loan losses, Modified in a troubled debt restructuring	6,168	5,444
Acquired with deteriorated credit quality	10,020	9,007	7,357	6,753
Loans:
Loans individually evaluated for impairment	1,892	51
Loans collectively evaluated for impairment	679,271	586,845
Acquired with deteriorated credit quality	694,517	600,065
Loans modified in a troubled debt restructuring	12,210	12,090
Total ending loans balance	694,517	600,065
Commercial Mortgages [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	1,144	1,079
Residential Real Estate [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	2,052	2,033
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	2,052	2,033	2,022	1,653
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	725,683	713,347
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	725,683	713,347
Residential Real Estate [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Consumer [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	2,065	2,179
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	2,065	2,179	2,089	2,215
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	77,981	80,193
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	77,981	80,193
Consumer [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Credit Cards [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	123	120
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	123	120	105	93
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	6,965	6,753
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	6,965	6,753
Credit Cards [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Overdrafts [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	214	194
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	214	194	$ 188	$ 188
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	1,134	352
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	1,134	352
Overdrafts [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	$ 0	$ 0